1. Field of the Invention
The present invention relates to articles having thereon, utilizing or employing a font and a method for representing Arabic characters. In particular, the present invention relates to articles which have thereon, utilizing or employing a font based system of characters representative of the extended Arabic characters that are generally symmetric to facilitate bi-directional use, uniform to render a single glyph per letter, and detachable to compose non cursive strings output.
2. The Prior Art
To represent the Arabic language digitally, mechanically or in ways other than by the common human hand writing, a minimum set of 44 basic glyphs must be created to represent the letters, diacritics and ligatures needed for reading and writing Arabic. Extended Arabic, used by more than 21 distinct non-Arabic languages (e.g. Urdu, Persian and Kurdish), contains some additional 96 basic glyphs, mostly derived from the original Arabic. Included are 9 diacritics that are required and must be represented by the basic glyph set. They are usually written on top or below a letter altering a letter or ligature glyph when viewed within fixed frame. These are not used extensively by modern Arabic. This means at least 140 distinct basic glyphs must be represented to accommodate all languages based on the extended Arabic (from now on Arabic) character set as defined by Unicode standards version 1.0.
In reality, each of the 140 glyphs above is an abstract representation of a letter, diacritic or a ligature. They mostly represent a distinctive shape (glyph) for a letter or ligature when written in its detached form. But when writing Arabic-based languages, each letter/ligature must change its shape, either significantly or slightly, depending on its position in a word. Some ligatures (e.g. Waw with Hamza above) belong to this basic set. Their position-dependent shapes are handled as if they were letters. Others (e.g. Lam-Alif) must be handled by replacing two basic glyphs with one glyph not included in the basic set. Therefore 2-5 glyphs in average are needed for each letter/ligature when writing these languages. The diacritics produce yet additional different shapes upon combination too.
Since each letter/ligature does not have one uniform shape in all positions, the number of glyphs needed is not constant and is dictated by type unlike in English (always 26 letters). Depending on the calligraphy or type (front), the designer must produce 400-600 distinct glyphs in order to accommodate electronically all these languages. See FIG. 9 for the case of Arabic language.
As a result, a huge number of glyphs would be needed in an article of manufacture with Arabic lettering embodied within (e.g. printer, computer, software and font type or stamping device). In addition, these articles must handle the problem of constant glyph substitutions using involved logical processes.
Arabic is normally read and written from right to left. It is no easily written or read from left to right. But in some applications (e.g. aviation field) training is provided to write it from left to right. Handwriting or reading Arabic from right to left is easy when acquired from childhood. But articles manufactured to utilize the Latin lettering (e.g. computer software and hardware) must be design-altered to accommodate the right to left direction mechanism. Also letters of embodied Arabic words on articles (e.g. transparencies, microfiche, negatives, image printing) look different depending on the direction of reading. Therefore bi-directional reading and writing is difficult using the right to left traditional Arabic lettering.
Unlike English, which is written both attached (script) and detached (regular print), the Arabic letters/ligatures are generally written in an attached form. Most letters/ligatures are attached (joined) with the letters to their right and the letters to their left. Some letters/glyphs must be detached (not joined) with letters on their left side but must be attached (joined) with letters on their right. Few letters/glyphs must be written detached from both sides. Also, in Arabic an optional glyph (Tatweel) of a straight horizontal line (like a dash) is used to prolong words lengths. It can form an arbitrary length. Articles of manufacture designed to produce Arabic lettering (e.g. computer software or hardware based articles) must involve extra and complicated logic or methods to handle the various puzzle-like letter joining and non-joining possibilities. Applications that need equal or fixed letter widths will not be able to handle traditional Arabic fonts easily.
U.S. Pat. No. 5,407,355 to Majzub discloses a method and font for representing Arabic characters. This invention discloses creating segments of characters and adding on to them to create different Arabic symbols. This is a burdensome and time consuming approach for use on articles such as office stationery.
U.S. Pat. No. 4,575,145 discloses an article having invertible lettering thereon. The invention is for the English language and relates to invertible lettering appearing on articles.
U.S. Pat. No. 4,244,657 to Wasylyk discloses a font and a method for printing cursive script in which all the letters are combined to form sets or subsets of individual letters of the font.
U.S. Pat. No. 5,295,238 to Dickson relates to a mathematical font for printing cursive character strings. Neither the patent of Wasylyk nor the patent of Dickson address the need to form fonts of non-cursive, separate distinct characters.
Accordingly, it would be desirable to provide a font and a method for articles to represent the extended Arabic letters as a fixed set of independent characters of unique glyphs which are generally symmetrical to facilitate bi-directional rendering and are detachable to allow non cursive strings input/output.
It is a principal object of the invention to provide a new distinctive Arabic based alphabets which introduce glyph symmetry and uniformity base and rule of design by representing each letter with one glyph of unique symmetrical and detachable look characteristics resembling traditional Arabic. Keeping this symmetry and uniformity base, one can produce variety of fonts belonging to this distinct alphabet. Changing the design of our glyphs, partially or totally, through systematic and geometric alteration of this base of symmetry found in each glyph will create new fonts to be utilized for their new look, direction suitability, or both, but still belong to the same distinct alphabets. Employing the invention eliminates all major and unique obstacles faced by articles of manufacture utilizing the traditional Arabic based alphabets. This font-only based, system-independent character input/output solution or method is intended to facilitate the use of Arabic lettering on articles designed for Latin lettering applications with a minimum or no alteration of the original design. Text written in these alphabets is readily legible to readers of traditional Arabic. Articles of manufacture with the embodiment of this new lettering (e.g. Latin or Arabic computer software and hardware, software translated into Arabic, transparencies, image printing, translation software, Arabic based languages teaching tools) can be produced with significantly less complexity to deliver Arabic in a form closely resembling the traditional Arabic.